多用户共信道信号的半盲闭式分离方法

该文充分利用数字移动通信系统中的已知短序列,给出了一种半盲多用户共信道信号分离方法。该方法首先得到信号的零空间,然后借助于各用户中的已知短序列,采用LMS算法得到各用户信号的估计。与非盲方法相比,所需的已知短序列非常有限,其最短长度仅为共用同一个信道的用户数。同时也克服了全盲方法运算量大和存在局部极小点等问题。计算机仿真实验表明,在多径条件下,该方法适用于智能天线系统中上行共信道信号的分离。

SEMI-BLIND CLOSED-FORM CO-CHANNEL SIGNALS SEPARATION METHOD

In this paper, a semi-blind closed-form co-channel signal separation method is proposed, which is based on two steps. The first is to estimate the zero space of multi-users signals. The second is to estimate them using LMS method and some short sequence, which is always known in digital communication system. Compared with non-blind ones, the new method needs very short sequence, the shortest length of which is equal to the number of co-channel users. At the same time it can overcome the shortcoming of blind ones in computational complexity and lack of global convergence. The computer simulation demonstrates that the new method is suitable for co-channel signal separation in smart antenna system when multipath exists.